This invention relates to a novel security and safety mechanism for firearms. More specifically, this invention relates to a security and safety mechanism that utilizes voice pattern recognition to selectively enable operation of a firearm to permit only an authorized user to fire the weapon.
One of the most frequently used classes of firearms by law enforcement agencies worldwide are semi-automatic handguns such as the 9 millimeter or 38 caliber semi-automatic weapons. Standard in these weapons is a thumb safety and grip safety which act to hinder unintentional firearm discharges. These mechanisms are almost universally used to provide a modicum of insurance against unintentional discharge of the weapon. The thumb safety operates by manually shifting the safety lever from its "safe" position to its "fire" position. The grip safety is automatically shifted to its "fire" position when the user's hand engages the stock of the weapon. Neither of these safety mechanisms is wholly effective to prevent the unauthorized use of the firearm, and these have proven unsatisfactory in dealing with a variety of safety concerns.
One area of safety concern is the complete prevention of accidental discharge so as to avoid unintentional injuries and/or death. Another safety concern involves weapons which come into the reach of children or inexperienced firearm users which are accidentally or improperly discharged resulting in serious injury and/or death. Further, a great concern of law enforcement officials is the unfortunate occurrence where a law enforcement officer is shot or killed with the officer's own service weapon. Such incidents most often occur during an attempted arrest of a violent subject who gains control of the officer's service weapon and then uses it against him. In all, 71 law enforcement officers were killed in the line of duty in 1991. Firearms were used in 68 of those slayings, including eight (11.3 percent) in which officers were killed with their own service weapons.
There have been several suggested measures to make firearms safer. These include loading indicators, increasing trigger pressure to make firearms more difficult to fire, automatic safety locks, and limits on muzzle velocity. However, these safety mechanisms still permit any individual, such as a child or criminal, to use the weapon if confiscated from an authorized user.
Some prior art devices utilize gun locks that require that a combination or code be entered into a key pad located on the weapon in order to allow the firing mechanism to operate. These devices are deficient because in a hostile situation the user would find it difficult to press the proper code keys. Furthermore, such devices are not unique to a given user because anyone who has the proper code entry could enable the weapon. A significant problem with these prior art devices is that if a law enforcement officer is disarmed of an enabled weapon (i.e. the code has been previously entered) during an altercation with a criminal suspect, the criminal could retrieve the enabled weapon and use it against the enforcement officer. Additionally, these devices require costly and difficult modifications to the firing mechanism and related structures.
There have been prior art attempts to provide a firearm with means to make that weapon operable only by specific authorized users. Some prior art devices require that the user wear a special signal generating component, such as a ring, bracelet, or glove. In these devices, the firing mechanism will only operate in the presence of a signal generated by the active device. These devices are deficient for several reasons. First, the active components are cumbersome and uncomfortable to wear, decreasing user acceptance and making the system less reliable. Furthermore, the devices are still not unique to a given user because the weapon would still operate for anyone who had the required signal generator. Still further, the weapon cannot be enabled quickly if the user is not presently wearing the signal generating device. Additionally, the incorporation of the disabling mechanism of these devices involves costly and difficult modifications to the firing mechanism. The firing mechanism of a semiautomatic handgun is a precise and delicate structure. The action of the handgun depends on a precise combination of factors such as muzzle pressures, component mass, and hammer spring tension. More modern designs are further complicated through the use of composite materials and sealed firing pin chambers. Modification of the firing mechanism to incorporate additional safety devices is a difficult and undesirable process.
Another prior art attempt to provide an improved safety mechanism overcame the problems associated with a separate signal generating means by utilizing palm or finger print information. In this device, a scanning circuit scans a portion of the hand of an individual and compares the scanned pattern with a stored pattern. A blocking mechanism for blocking movement of the firing hammer is only removed when a scanned pattern matches a stored pattern of an authorized user. This device is deficient because it is unreliable in use. If an officer needed to utilize his weapon in a hostile situation, he would be forced to await a recognition signal before the blocking mechanism would free the firing hammer. Furthermore, the scanning element would easily be weathered and damaged thereby decreasing the reliability of the device. As with other prior art devices, this device is further deficient because it involves costly and difficult alterations to the firing pin mechanism.
The difficulties suggested in the preceding are not intended to be exhaustive but rather among many which may tend to reduce the effectiveness and satisfaction with prior security and safety systems for firearms. Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that firearm security and safety systems of the past will admit to worthwhile improvement.